Heretofore, a connector to be attached to a tank (liquid storing container) for storing a drug solution or the like used for semiconductor production has been known (e.g., see Japanese Unexamined Patent Application, Publication No. H11-193894 (hereinafter referred to as “JP H11-193894”)).
The connector disclosed in JP H11-193894 includes a tank-side connector 1 in which a ring 7 that is provided with one or more keys 8 is buried, and a hose-side socket 2 having an outer peripheral surface in which a key groove 25 is formed at a position corresponding to the one or more keys 8. According to JP H11-193894, the key groove 25 of the hose-side socket 2 is formed at the position corresponding to one of more keys 8 of the tank-side connector 1, thereby preventing occurrence of a failure of an improper connection of the hose-side socket 2 that is incompatible with the one or more keys 8 of the tank-side connector 1.